A novel control strategy for electric spring-based multisource generation system

This paper proposes a combined source and load-side power management strategy for power control in an electric spring-based isolated hybrid system. The literature shows that the electric spring's operating range dramatically depends on the critical load (CL) to non-critical load (NCL) ratio and the minimum voltage level set for the NCL. To get a more excellent operating range, either NCL has to be large enough, or the minimum NCL voltage has to be set to a lower value. This work finds this gap and proposes a combined control strategy that utilizes SSPM and LSPM techniques to improve the NCL voltage. The proposed control scheme maintains the NCL voltage profile well above the minimum voltage of 170 V. In contrast, without the proposed control scheme, the NCL voltage reduces to around 120 V during a power shortage. Case-I evaluates the system's performance with nearly 100 % battery state of charge SoC. The switching of control from combined control to only LSPM control in low battery SoC conditions is studied in Case II. Also, a comparative study of the system performance with and without proposed control is given in this article. The work is modeled and simulated using Matlab and verified using OPAL-RT 5700.